Denmark patent No. 106,072 discloses an automobile steering lock bar, in which a pair of telescoping hook members may selectively be attached to opposite sides of a steering wheel. When the device is mounted and locked on the steering wheel, a bar projects outwardly from the steering wheel rim, and thereby limits the angle about which the steering wheel can be rotated. This effectively prevents the car from being driven with the bar in place.
In the 1970's, automobile security devices were introduced that lock the steering wheel to the floor brake pedal. Such devices employ a stationary lock housing which supports one hook member, and a serrated, telescoping rod which supports another hook member. With the lock released, the bar can be freely extended from the lock housing and the two hooks can thus be moved toward and away from one another. To mount the device, the hooks are positioned adjacent the steering wheel rim and brake pedal, and then pushed toward one another until they engage the steering wheel and brake pedal, respectively. Thereafter, the lock cylinder is turned to lock the rod in place.
Commonly owned U.S. Pat. No. 4,747,279 discloses a steering wheel mounted lock bar, similar to that disclosed in the Danish patent, except that the known serrated rod-telescoping lock assembly is utilized to carry the respective hook members. As in the case of the Danish patent, a bar projects from the steering wheel, when the device is mounted, to prevent the car from being driven. For further protection, one of the hook members is in the form of a lockable jaw mechanism, which locks around the rim on one side of the steering wheel, and thus renders the device more difficult even for a determined car thief to remove from the steering wheel. The assignee of the present invention markets this device under the trademark WB-40.